hello this is maybe a bit of an ask but would npc limb damage be possible? entry and exit wounds if the caliber is high enough and appropriate dismemberment. and add a gore level slider in the menu so people who dont like that they can just turn it down.

have you ever considered adding melee combat similar to chivalry medieval warfare?

craftable bow and arrow with retrievable arrows, but if you arnt planning on adding crafting thats alright.

swivel head , like the arma series being able to say hold down left alt and look around with just your head turning instead of your whole body . for this adds a ton of immersion to the game for me and im sure many others.
also since you are adding a character model

player medical system . maybe a menu with an interactive full body xray diagram to choose how to treat your wounds. there a mod for arma 3 called amg, its basic and effective im sure you guys already have a good concept but theres an idea.
if player gets an open wound there is a chance to leave a blood trail, a few small patches on the ground every few metres or so then from that goes on to player scent and ai tracking

i know its early days and will be added in time but a few different building types

maybe the ability to climb in and out of windows for when you get closed in by a zombie horde